Unless otherwise indicated herein, the description in this section is not prior art to the claims in this application and is not admitted to be prior art by inclusion in this section.
When there is an incoming call, a public-line network sends a call signal notifying the incoming call to a facsimile device via a telephone line. A telephone set is connected to the telephone line. According to a ring pattern of the call signal, the telephone set rings to notify the incoming call. When a facsimile device with automatic reception function detects the incoming call, a control unit that controls the incoming call counts the number of rings. When the number of rings reaches the specified number of rings, which is preset, the facsimile device automatically put the facsimile device off-hook and starts facsimile reception.
Some facsimile devices have an energy-saving mode. The energy-saving mode operates with reduced power consumption when a facsimile function is not used. Usually, in the energy-saving mode, it is operated that the control unit or a similar unit, which controls the incoming call, enters a sleep state and only functions to detect the incoming call from the public-line network and recover the control unit or a similar unit from the sleep state. Accordingly, there has been proposed a technique that controls the telephone set so as not to ring when the public-line network sends the call signal in the energy-saving mode.
When the incoming call is detected in the energy-saving mode, the control unit, which controls the incoming call, recovers from the sleep state and starts counting the number of rings. Accordingly, the number of rings from the incoming call being detected until the control unit recovers is not counted. This causes the number of rings more than the preset specified number of rings. Accordingly, techniques to prevent this have been variously proposed.
For example, there is proposed a technique that employs a ring control unit causing a telephone set to ring with a dummy bell signal generated corresponding to a call signal. In a normal mode, a main control unit controls the ring control unit to ring the telephone set by the specified number of times. In the energy-saving mode and during recovery from the energy-saving, a sub-control unit controls the ring control unit instead of the main control unit to ring the telephone set by the specified number of times.